Display panel portion with a graphical user interface



The FIGURE is a front view of a display panel portion with a graphical user interface according to the new design.

The outermost broken line rectangle showing a display panel portion of a computing device and all other broken lines showing portions of the graphical user interface do not form part of the claimed design. 

CLAIM The ornamental design for a display panel portion with a graphical user interface, as shown and described. 